The present invention relates to an amorphous core transformer, and more particularly, to an amorphous core transformer having a wound core (hereinafter referred to as the amorphous core) using amorphous magnetic strips.
The amorphous magnetic strip used for the amorphous core transformer has a very small thickness ranging from 0.022 to 0.025 mm and has the property of being high in hardness and brittle. Furthermore, as the material of the amorphous magnetic strip, a material with an amorphous sheet wound in a roll shape is used, however, the properties vary.
Also, there is known an amorphous core transformer in which the amorphous magnetic strips are wound to form a wound core. For example, in an amorphous core transformer for three phase 1000 KVA having a three-phase five-legged core as shown in FIG. 8, wound cores 50a to 50h and coils 40a to 40c are housed within a transformer tank container.
As for the wound cores, the amorphous magnetic strips are wound to form a unit core of approximately 170 mm in width and approximately 16200 mm2 in cross-sectional area. The unit cores are aligned in two rows widthwise of the strips, and four sets of unit cores, all eight pieces, are used.
An outer unit core located on each side has a core window with the coil of one phase disposed therein, while each of two inner unit cores has a core window with the coils of two phases disposed therein. Therefore, the masses of the inner unit cores and the outer unit cores are about 158 kg and about 142 kg, respectively, the inner unit cores being greater in mass and outer peripheral length than the outer unit cores.
A core coil assembly is composed of the eight unit cores 50a to 50h and the three coils 40a to 40c, as shown in FIG. 8. Each of the unit cores has a U-shaped cross-section so as to permit its insertion into the coils. After insertion, the ends are closed (subjected to wrapping operation), thereby assembling the core and the coil.
Within the coils 40a to 40c, there are installed bobbins 60a to 60f, two for each coil. As shown in FIG. 9, each of the unit cores 50a to 50h is opened on one side. The unit core of an inverted U-shape is inserted into the corresponding coil, and the opened portion is wrapped to assemble the core and the coil.
The coil bobbins are made of metal such as iron and formed in hollow square poles. As described above, two bobbins for each coil are arranged side by side.
Next, FIG. 10 shows a horizontal sectional view of the related art core coil assembly shown in FIG. 8.
Referring to FIG. 10, the coils of three phases are formed of the outer secondary coils 40a, 40b, and 40c and primary coils 40d, 40e, and 40f. The bobbins, with two bobbins for each coil arranged side by side, are installed in the coils. More specifically, the bobbins 60a and 60b are installed in the coils 40a and 40d, the bobbins 60c and 60d are installed in the coils 40b and 40e, and the bobbins 60e and 60f are installed in the coils 40c and 40f. Then the amorphous cores are inserted into the bobbins.
The core 50a is inserted into one side of the bobbin 60a installed in the coils 40a and 40d on the left side in FIG. 10, and the core 50b is inserted into one side of the bobbin 60b. 
The cores 50a and 50b are inserted into one side of the bobbins 60a and 60b, respectively, in such a manner that the cores 50a and 50b of the inverted U-shapes straddle the left edges of the coils 40a and 40d. Then left portions of the cores 50a and 50b located outside of the coil 40a are received by an E-shaped clamp 70 so as to keep their assembled conditions, and thereafter held and fixed from above by a U-shaped clamp 80.
This construction on the left side is applied in the same manner to the cores 50g and 50h on the right side to fix the cores 50g and 50h. 
The core 50c on the left-center lower side is inserted into the other side of the bobbin 60a and one side of the bobbin 60c installed in the coils 40a and 40d and the coils 40b and 40e, respectively, in such a manner as to straddle the portion where the coils 40a and 40d and the coils 40b and 40e are adjacent to each other. In the same manner, the core 50d on the left-center upper side is inserted into the other side of the bobbin 60b and one side of the bobbin 60d installed in the coils 40a and 40d and the coils 40b and 40e, respectively, in such a manner as to straddle the portion where the coils 40a and 40d and the coils 40b and 40e are adjacent to each other.
The core 50e on the right-center lower side is inserted into the other side of the bobbin 60c and one side of the bobbin 60e installed in the coils 40b and 40e and the coils 40c and 40f, respectively, in such a manner as to straddle the portion where the coils 40b and 40e and the coils 40c and 40f are adjacent to each other. In the same manner, the core 50f on the right-center upper side is inserted into the other side of the bobbin 60d and one side of the bobbin 60f installed in coils 40b and 40e and the coils 40c and 40f, respectively.
The core 50g on the right side is inserted into the other side of the bobbin 60e installed in the coils 40c and 40f and a portion of the E-shaped clamp 70 installed outside the coils 40c and 40f, in such a manner as to straddle the right edge portions of the coils 40c and 40f. Also, the core 50h is inserted into the other side of the bobbin 60f installed in the coils 40c and 40f and a portion of the E-shaped clamp 70 installed outside the coils 40c and 40f, in such a manner as to straddle the right edge portions of the coils 40c and 40f. The cores 50g and 50h received by the E-shaped clamp 70 are fixed from above by the U-shaped clamp 80.
Here, the related art core and bobbins are shown in FIGS. 11 and 12.
FIG. 11 shows the inverted U-shaped core 50a with one end of the unit core opened. In order to obtain more core cross-sectional area with the cores the same in width, two rows of the cores having the same width as described above are inserted into the two bobbins 60a and 60b arranged side by side as shown in FIG. 12 so as to compose the core coil assembly.
In the related art, in order to increase the core width and core cross-sectional area of the amorphous core transformer, the eight unit cores made of the amorphous magnetic strips having the same width are aligned in two rows as described above to compose the amorphous core transformer.
Unfortunately, this related art construction has been inefficient in operation because wrapping operations of eight cores for a single transformer are necessary to assemble the core coil assembly.